Phosphate materials having nano porous structure, preparation method therefor and use thereof

Abstract

Provided are a phosphate material with a nanoporous structure, a preparation method therefor and a use thereof. It has a chemical formula of Mn 1-x Fe x PO 4 , (0.01≤x≤0.99) and has a particle size of at most 50 nm and a porous structure. Also provided is a phosphate material having a general chemical formula of Mn 1-a-b Fe a M b PO 4 , wherein M is one or more selected from the group consisting of Mg, Ti, V, Cr, Co, Ni, Zn, Ga, Al, Zr, Nb, Mo, Sn, Sb, Ca, Ba, Sr, B, Ru, Si, Te, Nb, Cu and Li, and preferably a combination of five or more of the elements, 0.01≤a≤0.98, 10 −4 ≤b≤10 −2 , and the phosphate material has a particle size of at least 50 nm and has a porous structure. The material can be used for preparing a manganese iron phosphate battery cathode material, and the specific capacity, rate performance and cycle performance of the obtained anode material are improved.

1 .- 5 . (canceled) 
     
     
         6 . A phosphate material, wherein the phosphate material having a chemical formula of Mn 1-x Fe x PO 4  or Mn 1-a-b Fe a MbPO 4 , wherein 0.01≤x≤0.99, M is one or more selected from the group consisting of Mg, Ti, V, Cr, Co, Ni, Zn, Ga, Al, Zr, Nb, Mo, Sn, Sb, Ca, Ba, Sr, B, Ru, Si, Te, Cu and Li, and 0.01≤a≤0.98, 10 −4 ≤b≤10 −2 , the phosphate material having a particle size of at most 50 nm and having a porous structure. 
     
     
         7 . The phosphate material according to  claim 6 , wherein the particle size of the phosphate material is 5-40 nm. 
     
     
         8 . The phosphate material according to  claim 6 , wherein the phosphate material has a specific surface area of 10-30 m 2 /g and a pore size of 2-10 nm. 
     
     
         9 . The phosphate material according to  claim 6 , wherein, 0.2≤a≤0.5, 10 −3 ≤b≤10 −2 ; and/or, the phosphate material is monoclinic. 
     
     
         10 . (canceled) 
     
     
         11 . The phosphate material according to  claim 6 , wherein, the phosphate material having a chemical formula of Mn 1-a-b Fe a Co b PO 4 ; or
   Mn 1-a-b Fe a Mg b1 B b2 PO 4 , wherein  b 1+ b 2= b ; or     Mn 1-a-b Fe a Mo b1 Nb b2 B b3 PO 4 , wherein  b 1+ b 2+ b 3= b;        Mn 1-a-b Fe a Co b1 V b2 Ni b3 B b4 PO 4 , wherein  b 1+ b 2+ b 3+ b 4= b ; or     Mn 1-a-b Fe a Mg b PO 4 ; or     Mn 1-a-b Fe a V b1 Ti b2 PO 4 , wherein  b 1+ b 2= b;        wherein 10 −4   ≤b 1≤10 −2 , 10 −4   ≤b 2≤10 −2, 10   −4   ≤b 3≤10 −2 , 10 −4   ≤b 4≤10 −2 .
   
     
     
         12 . The phosphate material according to  claim 6 , wherein the phosphate material having a chemical formula of Mn 0.6 Fe 0.395 Co 0.005  PO 4  or Mn 0.65 Fe 0.344 Mg 0.005 B 0.001 PO 4  or Mn 0.7 Fe 0.293 Mo 0.003 Nb 0.003 B 0.001 PO 4  or Mn 0.8 Fe 0.19 Co 0.005 V 0.001 Ni 0.001 B 0.003 PO 4  or Mn 0.8 Fe 0.495 Mg 0.005  PO 4  or Mn 0.65 Fe 0.34 V 0.005 Ti 0.005  PO 4 . 
     
     
         13 . The phosphate material according to  claim 6 , wherein the M is five or more selected from the group consisting of Mg, Ti, V, Cr, Co, Ni, Zn, Ga, Al, Zr, Nb, Mo, Sn, Sb, Ca, Ba, Sr, B, Ru, Si, Te, Nb, Cu and Li. 
     
     
         14 . The phosphate material according to  claim 6 , wherein the phosphate material having a chemical formula of Mn 1-a-b Fe a Mg b1 V b2 Ti b3 Cr b4 Co b5 PO 4 , Mn 1-a-b Fe a Zn b1 Cu b2 Mg b3 Co b4 Ti b5 PO 4 , Mn 1-a-b Fe a Zn b1 Cu b2 Mg b3 Mo b4 Ti b5 PO 4 , Mn 1-a-b Fe a Mg b1 V b2 Ti b3 Cr b4 Mo b5 PO 4 , Mn 1-a-b Fe a Nb b1 B b2 Co b3 V b4 Al b5 PO 4 , Mn 1-a-b Fe a Co b1 V b2 Ni b3 B b4 Nb b5 PO 4 , Mn 1-a-b Fe a Co b1 Ga b2 B b3 Al b4 Sr b5 PO 4  or Mn 1-a-b Fe a Mo b1 Co b2 Ni b3 V b4 Ca b5 PO 4 , wherein b1+b2+b3+b4+b5=b, the ranges of b1-b5 satisfy 10 −4 ≤b1≤10 −2 , 10 −4 ≤b2≤10 −2 , 10 −4 ≤b3≤10 −2 , 10 −4 ≤b4≤10 −2 , and 10 −4 ≤b5≤10 −2 . 
     
     
         15 . The phosphate material according to  claim 6 , wherein the phosphate material having a chemical formula of
   Mn 0.7 Fe 0.293 Mg 0.015 V 0.001 Ti 0.0005 Cr 0.001 Co 0.003 PO 4 ,     Mn 0.6 Fe 0.395 Zn 0.001 Cu 0.0005 Mg 0.001 Co 0.002 Ti 0.0005  PO 4 ,     Mn 0.6 Fe 0.39 Zn 0.001 Cu 0.0005 Mg 0.005 Mo 0.003 Ti 0.0005 PO 4 ,     Mn 0.7 Fe 0.293 Mg 0.0015 V 0.001 Ti 0.0005 Cr 0.001 Mo 0.003 PO 4 , Mn 0.7 Fe 0.29 Nb 0.003 B 0.003 Co 0.001 V 0.002 Al 0.001 PO 4 ,     Mn 0.8 Fe 0.19 Co 0.005 V 0.001 Ni 0.0005 B 0.003 Nb 0.0005  PO 4 , Mn 0.5 Fe 0.49 Co 0.0025 Ga 0.0005 B 0.003 Al 0.002 Sr 0.002 PO 4 ,     or Mn 0.65 Fe 0.34 Mo 0.003 Co 0.003 Ni 0.002 V 0.0015  Ca 0.0005 PO 4 .   
     
     
         16 . A method for preparing the phosphate material according to  claim 6 , wherein the method comprising the following steps: 1) mixing a manganese iron oxide and an optional compound of an M element with phosphoric acid to obtain a reaction mixture; 2) grinding the reaction mixture and causing the reaction mixture to react to generate a phosphate to obtain a slurry containing the phosphate, wherein the particle size of the phosphate in the slurry is at most 100 nm; 3) separating the slurry to obtain phosphate particles; 4) drying and sintering the phosphate particles to obtain the phosphate material; wherein the M is one or more selected from the group consisting of Mg, Ti, V, Cr, Co, Ni, Zn, Ga, Al, Zr, Nb, Mo, Sn, Sb, Ca, Ba, Sr, B, Ru, Si, Te, Nb, Cu and Li. 
     
     
         17 . The method for preparing the phosphate material according to  claim 16 , wherein the particle size of the manganese iron oxide is 1-20 μm; and/or, the phosphoric acid is present in the form of an aqueous solution of phosphoric acid, and the aqueous solution of phosphoric acid has a mass concentration of 10%-70%. 
     
     
         18 . The method for preparing the phosphate material according to  claim 16 , wherein in step 1), the mixing is carried out under mechanical stirring at a temperature of 20-40° C.; and/or, in step 2), the grinding is carried out in a sand mill at a temperature of 20-40° C.; and/or, in step 4), the drying is carried out at a temperature of 100-120° C.; and/or, in step 4), the sintering is carried out at a temperature of 300-400° C.; and/or, step 3) comprises filtering and washing the slurry containing the phosphate. 
     
     
         19 . The method for preparing the phosphate material according to  claim 16 , wherein step 4) comprises: drying the phosphate particles to obtain a manganese iron phosphate monohydrate crystal or doped manganese iron phosphate monohydrate crystal with a particle size of at most 100 nm, and then sintering the manganese iron phosphate monohydrate crystal or the doped manganese iron phosphate monohydrate crystal to obtain the phosphate material. 
     
     
         20 . The method for preparing the phosphate material according to  claim 16 , wherein a ratio of the total molar quantity of the manganese iron oxide and the compound of the M element to the molar quantity of the phosphoric acid is 1:1 to 2. 
     
     
         21 . The method for preparing the phosphate material according to  claim 16 , wherein the method further comprising a step of pre-dispersing the manganese iron oxide in an aqueous solution of a dispersant, prior to step 1). 
     
     
         22 . The method for preparing the phosphate material according to  claim 21 , wherein the dispersant is one or more selected from the group consisting of polyvinyl pyrrolidone, polyethylene glycol and TC130 dispersant; and/or, the aqueous solution of the dispersant has a mass concentration of 0.01%-5%. 
     
     
         23 . The method for preparing the phosphate material according to  claim 16 , wherein the method further comprising a step of reacting phosphorus pentoxide with water to prepare the phosphoric acid, prior to step 1). 
     
     
         24 .- 29 . (canceled) 
     
     
         30 . A manganese iron phosphate battery cathode material, wherein the manganese iron phosphate battery cathode material is prepared by a high-temperature sintering reaction of raw materials comprising the phosphate material according to  claim 6 , and a lithium source compound and an optional organic carbon source. 
     
     
         31 .- 32 . (canceled) 
     
     
         33 . A lithium-ion battery, comprising a cathode material, wherein the cathode material comprises the manganese iron phosphate battery cathode material according to  claim 30 . 
     
     
         34 . The lithium-ion battery according to  claim 33 , wherein the lithium-ion battery having a specific discharge capacity of 145 mAh/g or more at 0.1 C, a specific discharge capacity of 135 mAh/g or more at 1 C, and a capacity retention of 92% or more after 200 cycles of charge and discharge at a 1 C.